title: [Continuous ultrasonic observation on the change of location of placenta in placenta previa].
abstract: Placenta previa was studied in 50 cases during 20-28 weeks of gestation by ultrasonic scanning. The change of location of placenta was monitored continuously for these cases. The rates of change of location to normal sites were 90% for low-lying placenta, 65% for marginal implantation, 13% for partial placenta previa and 11% for central placenta previa. It is suggested that partial or central placenta previa observed during mid-trimester should be categorized as a high risk state.
authors.affiliation: West China University of Medical Sciences, Chengdu.
authors.forename: W Z
authors.initials: WZ
authors.lastname: Li
authors.forename: T Z
authors.initials: TZ
authors.lastname: Yong
mesh_terms: D005260:Female; D006801:Humans; D010920:Placenta / Q000000981:diagnostic imaging*; D010923:Placenta Previa / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012307:Risk Factors; D016216:Ultrasonography, Prenatal